Thangka painting is the Tibetan Buddhist tradition of painting deities, mandalas, lineage masters and teaching diagrams on cloth scrolls, typically cotton or silk, framed with fabric borders and designed to be rolled for storage and transport, portability a practical necessity for a tradition that developed across a vast, often mountainous and historically nomadic religious landscape rather than one confined to fixed temple walls alone.
The discipline's defining technical constraint is iconometry, thig tshad, the system of measured proportional grids that fix the exact dimensions and placement of each element of a given figure, transmitted through dedicated iconometric manuals and through direct master to apprentice instruction, so that a properly executed thangka of a given deity or teacher follows prescribed proportion as exactly as a properly written icon follows its prototype in the Orthodox Christian tradition, artistic skill expressed within, rather than against, a fixed canonical structure. Painters traditionally undergo lengthy apprenticeship under an established master, learning first to grind and prepare mineral and organic pigments by hand, then to master the iconometric grid system, before being permitted to work on significant commissioned pieces, a training path that can extend over many years before a painter is considered fully qualified to execute major images independently.